Variable-pressure valve



Feb- 18, 1930- c..1. SIEFARTH VARIABLE PRESSURE VALVE 2 Sheets-Sheet Filed Feb. 13, 1923 Mq? M.

#VME/v TDR Feb- 18, 1930- l c. J. slr-:FARTH VARIABLE PRESSURE VALVE Filed Feb- 15, 1928 2 Sheets-Sheet 2 finaal/AV f Patented Feb. 1s, '1930 CHYESTEBIiJ. SIEFFETI-Ii, 'OF PORTLAND, '()REK'zrON-` Application ineay Februaryis, 1928. semi No. 253,875.

This invention rela-tes generally to valves,

' andV` pa rticularly.v to 'pressure-controlling devices.. p 'l The'l main object of .thisv invention visgto i' provide a simple, eitlcient and sensitive form oflvaria'ble"V pressurel valve by means `ofwhich y Aair.pressure may' be reduced Vand controlled;

automatically `andvcontinuously as. long as thel pressure from: thef'source of supply eX- ceeds'that to which the device is adjusted.V

, TheA second"'objectis .to reduceA the number ofpaits and special springs to the minimum and tof'so lconstruct same that theyl will bev yeasy to manufacture and"vv assemble and not 1'5.' subject.' tochatteringor vibrating, as is fre.

quent'lythecase with'devices ofthis nature.y

The third object is to so construct the de,` vicethat.V gradual applications ,and releases ofpressure can bejrsecured' by the mere positioning of'a hand lever. o

.The fourth objectV yis tozrequire' the em! ploynient otA only onemain operating spring,

anda small auxiliary spring having no other functionthan to'lioldfparts in' position when ,25? thesupply pressure isremoved.

*The fifth-object is to make it possible to secure ypractically the fullflowof air through f Ythe device from a. supply lineto a delivery y y,line*thereby enabling same to handle large f "quantitiesof airv in an `efficient manner.`

f These, and otherl objects, will become-'more apparent"I from thejspeci'fication follow-ing as illustrated inthe accompanying drawings,

' i inwhifch' f y 5,55 VFigure 1 isa vertical sectionjthrough the deviceina' normalpositfion, that is to say, with no vair flowing through same. kFigure ,Y 2 isa side elevation of the' devicey showing a portionof same insecti'on with the parts .in-position for the delivery ofv air at a reducedcontrolled pressure. Figure 3 is a detailed'vi'ew' ofthe operating nut. Figure 4 is a view similar to Figure 2 showing the parts/'inaI releasing positionin which air is i .l 5f not 7being' admittedfrorn' the source of sup-l ply butis being exhaustedi'from the element to/"wliich it was 'previously delivered and wasted to the atmosphere. y

planofthe'device. Figurev 6- is a section 591 taken alongthelne GE-Gn Fgureit :Figl- Figure' 5y is g a `Referring in detail. to the drawings, the

device may be divided into two principal parts, namely a body 10 and a capA 11, the two being oined by the screws 12 whicli'pass through the flanges 13 and 14 ofthe body 10 and thel cap 11.r

f lt willfbe assumed, for convenience, that' the valve is `just in the position shown y,in the drawings-that is with the-'body 10 lower# most. `Within the body lOis formed a' main cylinder 15 and at the lower endv thereof isl formed an extension 16 in' which is formed an auxiliary cylinder 17'whoselower end 18: opens to the atmosphere. 4

An air supply pipe 19 opens into the lowerv end of the main cylinder 15. The upper portion of the bodyy 10 is provided with a somewhat enlarged cavity 2OI above the cyl-` inder1'5 froml which opens a branch 21 to which is connected the delivery pipe 22 from which may be taken the controlled air, y

In the lowermost portion of the auxiliary `cylinder 17 is yplaced any auxiliary spring 23 which bearsagainst the' lower endv 18' of the member 16. Vithin the cylinder 17 is placed an auxiliary v'piston 24fprovided at its lower end with a cup leather 25, a cup'washer 26, a clampingscrew 27v and a lock, washer 28;

The piston 24 isf provided with an integral rod 29 around whose middle portion 30 is formed a valve seat ,31. Vilithin the cylinder 15 is placed the main piston'34 around whose cylindrical centralv opening 35 is formed an annular inletovalve 37 adapted to seat in the valve'seat y31 under certain conditions', which willbe explained later.

On the upper side of the piston 34 is -mounted. a cup' leather 38 whichk is heldin place vby the nut 391 Ribs` 40 on the side of the rod 29 guid'ethe upper end' of the rod 29' within the cylindrical opening 35: of the pi'ston'34.V Upon the nut 39, rests a heavy mainv spring 41 upon which depends almost entirely the task of' controlling the pressure delivery at the pipe 22. v 4 ThecapIfl is p'rovi'dedwitlrachamber'42 to which is connected the exhaust pipe 43.*'

yThe upper end 44 of the cap-11 is turned on the outside and counterbored on the inside frictional relation between these parts may 'be regulated by means of the screws 54.

Passing vertically through the operating screw 48 is a stem 55 whose shoulder 56 bears against the under side of the operating'scr'ew 48,. and whose upper end .is provided with a nutV 57 which permits rotation of the partsr 55 and 48. -Thelower end of the stem 55 is hollow and its recess 58 is provided with Ycommunicating passageways V59V which conf nectwith the chamber 42. ^At the extreme lower end of the stem and around the recess 58 is positioned the release valveseat (iOwhich. is adapted yto engage the valve 38 under certain conditions. A cup leather 61 ismounted inthe lowerY end of the cap 11 and bears against the outside of the stem 55 andis held in position bythe nut 62.

The operation of the device is as follows: When the lever 51 is moved to the positionl shown in Figure 1, which maybe either that of rest when no pressure'is applied to the valve or whenV the controlled supply has reached the pressure predetermined by the setting of the lever 51. It the lever 51 is now t moved in the direction indicated as apply in Figure 5 and there is an excess of pressure vavailable at the pipe 19 the parts now assume the position shown in Figure 2, that is, the inlet valve seat 81 has been pushed away from the inlet valve 87 permitting air to pass from the pipe 19l directly out Vthrough the pipe 22. However, as pressure `builds up inside of the enlargedV cavity 2O the piston 34, with the assistance of the spring 41, again closes the inlet valve 37 until such a time as pressure has been reduced in some `manner* from thevdelivery pipe 22. This may, oi course, be eitherby leakage or actual .use o the air, as is well understood. j Y.

Should it now be desired to release or even reduce the pressure at the pipe 22 it is only necessary to move the lever 51 in the opposite direction, which will move the stem 55l to the position shown in Figure i-namely, with the inlet valve 37 closed4 andthe release valve open permitting either a free or restricted passage of air from the pipe 22 to the chamberV 42 from which it can be disposed of- Vthrough lthe pipe 43,v depending entirelyy upon the position of the lever 51.

Since these devices are often employed in connection with vibrating parts it is prefer- .pressure chamber.

able to rictionally hold the lever v51 by means y 'of the screws 54, as above suggested.

It can also be seen that the capacity of this device to handleair is restricted only by the size of the ypipes leading thereto, since the manner in which the valves are operated pro,-

only a limited longitudinal travel j of the parts.

For the sake'of convenience the chamber yvides almost a complete valve opening with e chamber, while the chamber 42 shall be referred to as the'exhaust chamber.

forms ofvariable pressure valves have been s0 It is, ofcourse, well understood that many constructed in the past in`which the objects j' herein attained were aimed at but accornplished' only with limited degrees of success. Theprincipal objection to earlier and exista5VA ing iorms of vthis device was the ydiiiiculty of 1 maintaining anything likea suitable work-ri ing relation between theparts, due principally to wear occasionedby the manner in which the Apressureswere regulated, result-` ing, in some cases, in devices which were extremely noisy on account of their unstable t controlling elements, it is'therefore'my intention to cover only `such forms and modiiications of this device as fall fairly within Vthe a main piston mount-ed invsaid body having j an opening formed therein, an auxiliarypiston mounted in said body having a piston rod thereon, anV inlet valve between said rod and -piston opening, a main spring against the opposite side of said piston from the inlet valve, a cap for said body, a stem mounted in saidfcap, a release valve formed between l the lower end of saidvstem and the upper end of said rod saidfstein' having an opening conl trolledby said release valve communicating ywith the exterior of said cap,fand means for aifecting the vertical position of said stem.

. 2. A. variable pressure valvehaving formed Y therein a high pressure chamber, a controlled,

pressure chamberand an exhaust chamber all in axial alignment, a piston between said*V ,high pressure chamber and .controlled pressure chamber'having'an opening therein, a

double valve within said piston onel side of which closes saidpiston opening from its high pressure side and the other'sideof saidV valve projecting intosaid controlled pressure chamber, an axially vr slidable outlet Vstemr adapted to be closed by the valve in said con-4 trolled pressure chamber', means for slidably f positioning said outlet stem,'and a main spring. urging said piston 'toward the high 3.l A variablepressure valve consisting of a .body having a highpressure and Ya controlled pressure chamber formed therein, a piston slidablyv mounted between said high .and lowpressure chambers, a main spring urging said piston toward said high pressure chamber, saidV piston having an opening formed therein havingy a closing valve on its high pressure side, said closing valve lhaving y a 'release valve attached thereto projecting y intosaid controlled .pressure chamber, a hollow stem projecting through said body into 'said' controlled pressure chamberadapted to be closed by said'release valve when in en-v gagement therewith, and meansfor slidably f positioning said hollow stem.

4. Avariable pressure valve consisting of a ybody having a cylindrical high pressure let valve for said opening slidably mounted therein, a releasevalve connecting with said 'j inlet valve andV projecting through the opposite end of said piston, a hollow stem passring through said body 'adapted to be closed by said release valve, a main spring urging said piston toward said inlet valve, and manualy operated screw means for slidably positioning said stem for the purpose of varying the compression oi said main spring.

5. A variable pressure valveconsisting of a body having a controlled pressure chamber l formed at the top thereof, a high pressure chamber formed at the middle thereof and having a piston forming one end of said high pressure chamber, said piston having aii opening formed through same, a balanced vinlet valve against the underside of said piston opening having means for slidably mounting Y saine in the lowermost part of said body and in the piston opening, a release valve integral with said inlet valve projecting into said controlled pressure chamber, a main spring on said piston, a cap over said main spring, fforming a closure for said body, said cap havying an exhaust lChamber formed therein, a

hollow' control stem passing downwardly lthrough said cap and chamber having its lower end adapted to seat upon said release valve 'and having side outlets thereincommunicat-ing with said exhaust chamber, and a y screwfeedforadjusting the vertical height Voit said stem, said high pressure chamber having van inlet supply pipe attached thereto, said controlled pressure chamber having a delivery pipe attached thereto.

6. A variable pressure valve having a cy- *lindrical body member, a balanced inlet valve mounted in the lower endot1 said body meml ber, a piston slidably. mounted in said body having an openingy therein adapted to be closed by said inlet valve, said body having ,an inlet opening for' admitting high pressure air to theinlet valve side of said piston,

.- Va main spring on the upper side of said pisal ton urging same to seat upon said inlet valve,

a release valve integral with said inlet valve extending upwardly through `said piston opening a vertically slidable control stem projecting through said body and seating upon said release valve, screw means for moving said stem, vertically, and a handle for rotating said screw. c

7. A variable pressure valve having a body and having disposed therein in successive order a balanced inlet valve, a ported piston lever for rotating said sleeve in a manner` to vary the compression of said main spring ifor'the purpose of controlling the pressure whichcan be built up around said main spring, and means for delivering air from the chamber containing said main spring to an outside device.

8. A variable pressure valve having a high pressure chamber, a controlled pressure chamber and an exhaust chamber formed therein withfcommunicating pipe lines therefor, a ported piston slidably mounted therein between said high pressure chamber and said controlled pressure chamber, a-control valve stem having a tubular end slidably projecting into said controlled pressure chamber, a balanced double valve slidably mounted in said piston the top side of which forms a closure for said control valve stem and the bottom side of which forms a closure tor said piston, and manually operated means for slidably positioning said control valve stem for the purpose of determining the pressure at which said inlet valve will close the port in said piston.

9. A variable pressure valve having in combination a cylindrical body having mounted in the middle thereof a main piston provided with a central opening, an auxiliary piston mounted in the bottom thereof having a spring on its underside which under side is open to the atmosphere, an inlet valve on said auxiliary piston adapted to be balanced thereby, a release valve above said piston integral with said inlet valve, a main spring onk the top'side of said piston, an outlet in said body for the delivery of air from the top side of said piston, a second outlet adapted to be closed by said release valve, and means for adjusting the point at which said release valve shall close said last mentioned outlet.

l0. A variable pressure valve having in upon saidpiston, a cap upon said body formcombination a cylinder having'a high pressure chamber at one end thereof With an inlet thereto, a Controlled pressureV chamber at the other end thereof having an outlet therefrom, a main piston in said cylinder between said Chambers having a port formed therethrough, an auxiliary piston on one side of said high pressure chamber opposite said K main piston, said auxiliary piston having a rod extending through the port insaid main piston7 said rod having an inlet valve in said high pressure Chamber adapted topolose said port When said piston is moved downwardly, a main springin said controlled pressure chamber urging said` piston downwardly to a seat With said inlet valve, an auxiliary spring under said auxiliary piston urging said inlet valve to a seat With said main piston, means Vfor releasing air'lroin said Vcontrolled pressure chamber consisting ol' a slidable outlet tube extending,` into said controlled pressure chamber, n a release valve forming a closure for said outlet tube said release valve forming a part of said auxiliary piston and inlet valve, andmeans for manually adjusting the amount which said outlet tube projects into said controlled pressure chamber. Y o

CHESTER J. K SIEFARTH. 

